The objective of this proposal is to continue to provide core research and service support to the comprehensive clinical studies of the National Prostatic Cancer Project. A series of uniform biological marker tests, which have been showen to be relevant to monitoring the efficacy of prostate cancer treatment and management, are to be offered for all patients in various treatment protocols. An objective and improved clinicopathological evaluation will be performed from clinical information compiled at the Statistical Office, National Prostatic Cancer Project, and from a standard set of tests which are not readily available in participating centers locally. Specifically, we propose to measure serum bone alkaline phosphatase isoenzymes, liver alkaline phosphatase isoenzyme and a newly reported prostate antigen as well as prostatic acid phosphatase. Additional new biomarkers or assay procedures, which will indicate improved and/or additive clinical values in monitoring the treatment of prostate cancer, can be added to the list of tests as they become available. Furthermore, establishment of a serum bank will be continued to provide a biological resource for prostate cancer research. The purpose of this renewal application is to continue the core function of this central laboratory, which has made major accomplishments and played an essential role in the continued success of the clinical trials of the National Prostatic Cancer Project.